We are focusing on a novel pathway that regulates mitochondrial function and cardiovascular exercise capacity with implications for tumorigenesis. We have shown that the tumor suppressor gene p53 balances the energy generated by respiration and glycolysis and that this effect is primarily mediated through its regulation of mitochondrial function. Interestingly, mice deficient in p53 display profound deficiencies in aerobic exercise capacity revealing a new function for a well-studied gene mainly associated with cell cycle and genomic regulation. We are further characterizing the biology underlying these observations and translating them to humans through clinical studies. We are also continuing our translational studies on inflammation and atherosclerosis that was initiated by the genetic screen of easily accessible patient samples.